BS: Roman Numerals-analogue decimal mantissa

Subject: BS: Roman Numerals-analogue decimal mantissa
From: Mr Red
Date: 10 Jul 19 - 02:31 PM

Never seen this before. Did the Romans ever use an analogue decimal mantissa? (aka fraction bit after the dot)

milestone image 2.5 Miles from St Austell, Cornwall.

The funny marks on top are a Rivet Bench Mark - height above sea level (mean at Newlyn in Cornwall) 81.0M or 267.0 ft in old money.

Subject: RE: BS: Roman Numerals-analogue decimal mantissa
From: DMcG
Date: 10 Jul 19 - 02:41 PM

No, as far as I know. The notation does not really support it, because it inherently needs some form of positional notation. X.VII would be very ambiguous. What you could do is have one or more 'fixed fractions', so that X.VII might always mean 10 and 7/100s, for example. And arguably the old pounds/shillings/pence notation was like that: P pounds plus (S + D/12)/20 more pounds

Subject: RE: BS: Roman Numerals-analogue decimal mantissa
From: Mr Red
Date: 10 Jul 19 - 03:22 PM

This was something like (I am experimenting here)

S^t Austell
    III


I have seen images of a few similar milestones from around Cornwall. Even one that had regular numerals for one destination and Roman for the other.

Subject: RE: BS: Roman Numerals-analogue decimal mantissa
From: Jack Campin
Date: 10 Jul 19 - 05:21 PM

Two and a half?

Subject: RE: BS: Roman Numerals-analogue decimal mantissa
From: Mrrzy
Date: 10 Jul 19 - 06:03 PM

When we were being taught to do arithmetic in roman numerals, we were told the romans had no decimal point or numbers after it.

Subject: RE: BS: Roman Numerals-analogue decimal mantissa
From: punkfolkrocker
Date: 10 Jul 19 - 08:47 PM

Is Cornwall still a popular holiday destination for ancient Romans...???

Subject: RE: BS: Roman Numerals-analogue decimal mantissa
From: DMcG
Date: 11 Jul 19 - 01:46 AM

I will try to Express what I said before in a different way which may be less obscure. It is very likely that the Romans (and whoever made that stone who was probably no more Roman than I am) wanted to represent something like "two long measures and one short measure." Quite a lot of our older measurement systems do that: miles, chains, yards, feet; gills, pecks, bushels and quarrers; stones and pounds and ounces. By having all these different categories you avoid fractions (and very large numbers) which arise if you try to express everything in a single unit. The decimal point is an evolution of the fraction, in many ways

So in short, the Romans avoided anything like a decimal point by using "mixed units" in measurements.

Subject: RE: BS: Roman Numerals-analogue decimal mantissa
From: Mr Red
Date: 11 Jul 19 - 05:15 AM

Just a thought, but did the Romans ever conquer Kernow?

They probably visited as tourists, just as they did in Ireland. But encamp?

Subject: RE: BS: Roman Numerals-analogue decimal mantissa
From: Jon Freeman
Date: 11 Jul 19 - 06:19 PM

Roman Fractions

Subject: RE: BS: Roman Numerals-analogue decimal mantissa
From: DaveRo
Date: 12 Jul 19 - 03:00 AM

This milestone will have been made in the 18th Century when the turnpike to St Austell was built. I see that there are others of a similar pattern.

Maybe a local mason invented this notation. Maybe it was two and some lads walking back from the pub thought it should be three so started to increment it, before being interrupted.

You could ask the Milestone Society.

Subject: RE: BS: Roman Numerals-analogue decimal mantissa
From: Steve Shaw
Date: 12 Jul 19 - 04:49 AM

There are not many signs of "Romanisation" in Cornwall. The extent of Roman influence or settlement is often argued about by historians. The saint who gave his name to St Austell is not mentioned until the tenth century. The original saint name ended with a single letter l (St Austol) but the (mis)spelling on the stone is odd.

Subject: RE: BS: Roman Numerals-analogue decimal mantissa
From: Howard Jones
Date: 12 Jul 19 - 05:02 AM

If this is from a milestone then the small number may have represented a smaller measure, eg a furlong (1/8 of a mile) rather than a fraction of a mile. This is how distances were usually shown in pre-decimal days. So this might mean "Two miles and one furlong"

Subject: RE: BS: Roman Numerals-analogue decimal mantissa
From: Iains
Date: 12 Jul 19 - 05:19 AM

It is interesting that the Romans took over lead mining in the Mendips within a few years of invading Britain but as far as I am aware there is no direct evidence of their involvement in the tin mines of Cornwall. "Tin mining may have been in local hands, with tin purchased by the imperial authority. A possible official stamp has been identified on the Carnington tin ingot. A number of tin ingots have been found in Roman contexts, such as 42 found in a wreck at Bigbury Bay in 1991–92.
A site in the Erme Valley, Devon, shows sediment aggregation in late Roman and Post-Roman times due to tin mining on Dartmoor. The latter may well coincide with reduced production from Spanish mines.

Subject: RE: BS: Roman Numerals-analogue decimal mantissa
From: DMcG
Date: 12 Jul 19 - 06:53 AM

I realise this is getting horrendously close to hair splitting, but the link on Roman Factions is talking about working in twelfths, for example. To my mind, that is more of the mixed unit idea. There is a fixed big unit and a fixed small unit. To fully get into fractions, both the numerator and denominator need to be free: so I could talk about 13/19th if I chose. So while the fractional system that it talks about is on the way to a full fractional system, it is not quite there.

Subject: RE: BS: Roman Numerals-analogue decimal mantissa
From: Jon Freeman
Date: 12 Jul 19 - 07:36 AM

That's a reasonable observation Dave.

But you could try this calculator to get to other fractions...

Subject: RE: BS: Roman Numerals-analogue decimal mantissa
From: punkfolkrocker
Date: 12 Jul 19 - 08:22 AM

anyone still using a slide rule...???

Subject: RE: BS: Roman Numerals-analogue decimal mantissa
From: Mr Red
Date: 12 Jul 19 - 08:32 AM

It is interesting that while Roman integers where in steps of 1, 5, 10, 50 100 etc, (ya gotta hand it to them) but their fractions were in twelths. I can understand where the five comes from and twelths afford dividing the spoils between three (etc) people but ..............

Maybe the women got that franchise............


I'll get my chariot.

Subject: RE: BS: Roman Numerals-analogue decimal mantissa
From: Steve Shaw
Date: 12 Jul 19 - 08:34 AM

Nah. Just log tables.

Subject: RE: BS: Roman Numerals-analogue decimal mantissa
From: Jon Freeman
Date: 12 Jul 19 - 08:39 AM

Not me. I was given one in my 1st year of secondary school but never really used it or got to grips with it. Just the old books of tables for me.

These days I have a Casio scientific calculator on my desk. No great or frequent mathematical needs but I like it for example if an odd attempt at programming takes me to binary or hex.

Subject: RE: BS: Roman Numerals-analogue decimal mantissa
From: Mr Red
Date: 12 Jul 19 - 09:23 AM

In Excel there are functions for that, but then I am usually in Excel so just type it in a cell. It is quicker than going to the calculator because there is a richer set of functions. And in VBA you can work in any modulo. I have one website that runs to modulo 189 - because that is nearly the maximum of single byte characters in a text variable that JavaScript can handle without belching. Hex no problem until I have to do arithmetic in it. But then there is always Excel (& VBA).

Now. Anyone still able to use a slide rule? I wonder how the Romans would have handled logarithms? The Arabs & Indians could.

Subject: RE: BS: Roman Numerals-analogue decimal mantissa
From: Mrrzy
Date: 12 Jul 19 - 02:02 PM

I had to use a slide rule in hihh school. Pesky decimal point.

Subject: RE: BS: Roman Numerals-analogue decimal mantissa
From: punkfolkrocker
Date: 12 Jul 19 - 02:09 PM

I was crap at maths..
The maths teacher was a rugger bugger sadist who had it in for me
because I had long hair and skived PE & games to practice guitar and show off to girls...

But eventually, I did become quite reliant on my slide rule..

These days, I can't remember how to do long division, even using a calculator...